In a Patent Document 1, there is described a technology in which in a system where an electric generator is caused to actuate utilizing kinetic energy of wheels at the time of deceleration running of a vehicle, a pumping loss of an internal combustion engine is changed according to a change in an amount of electric power generated by the electric generator (an amount of regeneration).
In a Patent Document 2, there is described a technology in which in a system where a fuel injection amount learning value is obtained on the basis of an idle injection amount reference value, so that an engine rotational speed can be controlled to a target idle engine rotational speed, the fuel injection amount learning value is obtained after correcting the idle injection amount reference value according to operating states of accessories (auxiliary machines) or a temperature of cooling water.
In a Patent Document 3, there is described a technology in which in a system where a fall in temperature of a catalyst is suppressed by decreasing an amount of intake air sucked into an internal combustion engine at the time of deceleration running of a vehicle, a pumping loss of the internal combustion engine is made to be reduced by regulating opening and closing timing of intake valves, so that an amount of regeneration of kinetic energy is made to increase.
In a Patent Document 4, there is described a technology in which the timing at that a voltage generated by an electric generator is changed to a low generated voltage from a standard generated voltage is made to be synchronized with the timing at that fuel injection is caused to resume from a fuel cut off state, so that a rotational variation of an internal combustion engine associated with a change of generated voltage is made to be reduced.